"And this is not a commitment," he notes on his prediction. "Nor is it, by the way, the Fed's statement on the end of 2014 as a timeframe for low rates, by the way. It is a forecast, and just as a forecast normally does, it should vary sensitively to conditions of the economy. It may be sooner that we raise rates."

Asked on whether that forecast includes unemployment well below 8 percent he says, "It is a real possibility that unemployment could go below 8 percent."

"We need to raise rates before that time where a rate of over 8 percent becomes the sustained rate of unemployment. Look, inflationary pressures increase even when unemployment is at that level," Lacker says, pointing at a major difference with Fed Chairman Bernanke.